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WorldStuntTeam
01-18-2008, 10:10 PM
I own an HVX200 so I should know this stuff but I am still not clear on the whole data rate transfer thing. I understand the higher data rate of 100mbps with the HVX is better than lets say HDVs 25mbps but exactly why?

How does data rate effect video recording and why?

Andrew McCarrick
01-18-2008, 10:19 PM
The higher data rate allows for a higher color space; DVCPro HD (4:2:2) compared to HDV (4:2:0), Intra-Frame recording (whole frames) compared to Inter-Frame recording (whole frames only 12 or 15 frames, and partial frames for the intermediate frames.), I'm sure there are others, but for me those two alone are more than enough to DVCPro HD instead of HDV.

ProfessorU
01-19-2008, 10:03 AM
At the risk of repeating AlienFX, Data is detail. In the DVCProHD vs HDV comparison, DVCPro uses that extra detail for:
1) Much better temporal performance. In pictures that change rapidly over time (like fast pans, fast moving objects, flashes, explosions, etc.) you will see less detail in each frame in a HDV format.
2) Higher chroma resolution. Fine color changes are lost on HDV. Many people won't see this on a TV, but performing additional processes on the color in the footage (like chromakeying, color grading, etc.) will make the footage look blocky on HDV video.
3) More channels of higher quality audio. HDV uses "perceptually lossless" compression, which means that if you're not processing the audio, you probably won't notice any difference in the final sound quality, but if you want to add gain, compression, etc. you'll notice that the sound quality isn't as faithful to the original. In addition, DVCProHD records 4 channels of audio instead of 2.

WorldStuntTeam
01-19-2008, 06:32 PM
Thanks for your answer. How do I update my firmware on my HVX200 or P2 store? Never even heard of that before now...

WorldStuntTeam
01-19-2008, 06:34 PM
Never mind, I followed the link in your signature...